The present invention relates to a power-driven hand-held fastener driving machine such as a tacker, and more particularly to a safety device on such a fastener driving machine.
One known safety device for fastener driving machines is disclosd in U.S. Pat. No. 3,905,535. The disclosed safety device includes a linkage which actuates a control valve assembly in response to engagement of a linkage end with a workpiece. The illustrated fastener driving machine also has a quick release assembly for obtaining access to a drive track as when removing a staple jam. While the quick release assembly is actuated to open the drive track to remove a jammed staple, however, the operator tends to touch the linkage end for thereby tripping the control valve assembly. This is dangerous expecially when the operator happens to touch a trigger.
Other forms of drive track access mechanisms are disclosed in U.S. Pat. Nos. 3,273,777, 4,139,137, and 4,200,215. However, the revealed drive track access mechanisms have proven unsatisfactory in that they are relatively complex in structure and cannot easily be actuated.